Ovid Language

A toy programming language.

See lang.md for a description of the language.

The examples directory contains a few example ovid programs.

Building

Building Ovid requires:

• CMake >= 3.15.3
• A C++-17 compliant compiler
• LLVM >= 10.0.0
  • Only the LLVM Core libraries are required

Ovid's runtime requires:

• The Boehm GC

To build and install the main executable (ovidc):

mkdir build
cd build
cmake ..
cmake --build .
sudo cmake --install .

To build and run ovid's test framework:

mkdir build
cd build
cmake -DENABLE_TESTING=ON ..
cmake --build .
sudo cmake --install .
./runUnitTests
./runTests ../tests

Usage

ovidc --help

Usage: ovidc [OPTIONS] file...
The Ovid Language Compiler Backend
Options:
  -h, --help             Display this message
  -o, --output FILE      Output compilation results in FILE
  -c, --emit-obj         Produce object code output
  -S, --emit-asm         Produce assembly output
  --emit-llvm            Produce LLVM IR output
  -O, --opt-level OPT    Set the optimization level:
    0  no optimization
    1  optimize without greatly increasing compile time
    2  optimize without greatly increasing output size
    3  optimize fully for speed
    s  optimize for output size
    z  optimize fully for output size
  --code-model MODEL     Set the code model to use:
    tiny, small, kernel, medium, large
  --reloc-model MODEL    Set the relocation mode to use:
    static, pic, dynamic-no-pic, ropi, rwpi, ropi-rwpi
  --dump-ast             Print the abstract syntax tree for the source code
  --dump-ir              Print the intermediate representation for the source code
  --dump-mono-ir         Print the monomorphic intermediate representation for the source code
  --dump-escape          Print escape analysis results
  --dump-llvm            Print unoptimized llvm ir
  --package NAME[:NAME]...
                         Set the package name
  --package-version VERSION
                         Set the package version (must be an integer)
  --main                 Generate a main function
  --no-main              Don't generate a main function (default)

Examples

• Compiling and running test.ovd (test.ovd must contain a pub fn main() -> i32):

ovidc --main -o test.o test.ovd
cc -o test test.o -lm -lgc -lovidruntime
./test

• Compiling lib.ovd as a library, and dumping debug info:

ovidc --no-main -o test.o --dump-ast --dump-ir --dump-escape --dump-llvm test.ovd 

Source Organization

• src - Ovid compiler source code
  • test_framework - The compiler's custom test framework
  • tokenizer.cpp, parser.cpp - Tokenizer and parser, which convert ovid files into abstract syntax trees
  • ast.hpp, ast_visitor.hpp - Abstract syntax tree (ast) definitions and utilities
  • symbols.hpp - Scope tables and utilities
  • resolve_pass.cpp - Identifier + Type Alias resolver -- operates on the ast, and manages the module system's rules
  • type_check.cpp - Checks types and converts ast to ir
  • ir.hpp, ir_visitor.hpp - Intermediate representation (ir) definitions and utilities. A linear instruction based representation
  • escape_analysis.cpp - Escape Analyzer, which determines which allocations are stack and which are heap
  • llvm_codegen.cpp, name_mangle.cpp - The llvm backend. Converts ir to llvm output.
  • error.cpp - Error printing utilities
  • *_printer.hpp - Debugging utilities
• runtime - Ovid runtime library (not much currently)
• tests - The compiler's testsuite. The tests are all ovid files, but use comment annotations to drive the test harness